Method and apparatus for entering a connected state with a network for continuing transmission in wireless communication system

ABSTRACT

A method and an apparatus for entering a connected state with a network for continuing transmission in a wireless communication system is provided. The method may include starting a Time Alignment Timer (TAT). The method may include leaving a connected state with a network. The method may include performing transmission with a configured grant, wherein the configured grant is received from the network, while in leaving the connected state. The method may include performing a random access (RA) to the network, after the TAT is expired.

BACKGROUND Technical Field

The present disclosure relates to a method and apparatus for entering aconnected state with a network for continuing transmission.

Related Art

3rd generation partnership project (3GPP) long-term evolution (LTE) is atechnology for enabling high-speed packet communications. Many schemeshave been proposed for the LTE objective including those that aim toreduce user and provider costs, improve service quality, and expand andimprove coverage and system capacity. The 3GPP LTE requires reduced costper bit, increased service availability, flexible use of a frequencyband, a simple structure, an open interface, and adequate powerconsumption of a terminal as an upper-level requirement.

Work has started in international telecommunication union (ITU) and 3GPPto develop requirements and specifications for new radio (NR) systems.3GPP has to identify and develop the technology components needed forsuccessfully standardizing the new RAT timely satisfying both the urgentmarket needs, and the more long-term requirements set forth by the ITUradio communication sector (ITU-R) international mobiletelecommunications (IMT)-2020 process. Further, the NR should be able touse any spectrum band ranging at least up to 100 GHz that may be madeavailable for wireless communications even in a more distant future.

The NR targets a single technical framework addressing all usagescenarios, requirements and deployment scenarios including enhancedmobile broadband (eMBB), massive machine-type-communications (mMTC),ultra-reliable and low latency communications (URLLC), etc. The NR shallbe inherently forward compatible.

In Rel-13, narrowband internet-of-things (NB-IoT) and LTE formachine-type communication (LTE-M) were standardized to providewide-area connectivity for IoT. The technologies in Rel-14 evolvedbeyond the basic functionality specified in Rel-13. In Rel-15, tooptimize the support for infrequent small data packet transmissions.

A mechanism for transmission of a wireless device while in leaving aconnected has been studied. A wireless device may use a configured grantfor transmission. This mechanism could improve the device battery lifeand reduce the resource for transmission.

SUMMARY

A wireless device may transmit data while in leaving a connected statewith a network using pre-allocated resource. However, when thepre-allocated resource is not valid and/or uplink timing is not alignedwith the network, a wireless device could not transmit uplink data usingthe pre-allocated resource. Therefore, a method for entering a connectedstate with the network for continuing transmission in wirelesscommunication system is required.

In an aspect, a method performed by a wireless device in a wirelesscommunication system is provided. The method may include starting a TimeAlignment Timer (TAT). The method may include leaving a connected statewith a network. The method may include performing transmission with aconfigured grant, wherein the configured grant is received from thenetwork, while in leaving the connected state. The method may includeperforming a random access (RA) to the network, after the TAT isexpired.

In another aspect, a wireless device in a wireless communication systemis provided. The wireless device may include a memory, a transceiver,and a processor, operably coupled to the memory and the transceiver. Theprocessor may be configured to start a Time Alignment Timer (TAT). Theprocessor may be configured to leave a connected state with a network.The processor may be configured to perform transmission with aconfigured grant, wherein the configured grant is received from thenetwork, while the wireless device leaves the connected state. Theprocessor may be configured to perform a random access (RA) to thenetwork, after the TAT is expired.

The present disclosure can have various advantageous effects.

According to some embodiments of the present disclosure, a wirelessdevice may continue to transmit data while in leaving a connected statewith a network, efficiently.

For example, according to some embodiments of the present disclosure, awireless device may enter a connected state with a network, when databecomes available and a pre-allocated resource cannot be used.

For example, according to some embodiments of the present disclosure, awireless device may enter a connected state with a network, when databecomes available and uplink timing is not aligned with the network.

For example, according to some embodiments of the present disclosure, awireless device may continue data transmission by reconfiguring resourcefor transmission and/or aligning UL timing with the network in aconnected state.

Advantageous effects which can be obtained through specific embodimentsof the present disclosure are not limited to the advantageous effectslisted above. For example, there may be a variety of technical effectsthat a person having ordinary skill in the related art can understandand/or derive from the present disclosure. Accordingly, the specificeffects of the present disclosure are not limited to those explicitlydescribed herein, but may include various effects that may be understoodor derived from the technical features of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows examples of 5G usage scenarios to which the technicalfeatures of the present disclosure can be applied.

FIG. 2 shows an example of a wireless communication system to which thetechnical features of the present disclosure can be applied.

FIG. 3 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

FIG. 5 shows a block diagram of a user plane protocol stack to which thetechnical features of the present disclosure can be applied.

FIG. 6 shows a block diagram of a control plane protocol stack to whichthe technical features of the present disclosure can be applied.

FIG. 7 shows an example of a connection resume procedure to which thetechnical features of the present disclosure can be applied.

FIG. 8 shows an example of a method for entering a connected state witha network for continuing transmission, according to some embodiments ofthe present disclosure.

FIG. 9 shows a flow chart of an example of a method for entering aconnected state with a network for continuing transmission, according tosome embodiments of the present disclosure.

FIG. 10 shows a method for entering a connected state with a network forcontinuing data transmission, according to some embodiments of thepresent disclosure.

FIG. 11 shows an apparatus for entering a connected state with a networkafter a TAT is expired, according to some embodiments of the presentdisclosure.

FIG. 12 shows an example of an AI device to which the technical featuresof the present disclosure can be applied.

FIG. 13 shows an example of an AI system to which the technical featuresof the present disclosure can be applied.

DESCRIPTION

The technical features described below may be used by a communicationstandard by the 3rd generation partnership project (3GPP)standardization organization, a communication standard by the instituteof electrical and electronics engineers (IEEE), etc. For example, thecommunication standards by the 3GPP standardization organization includelong-term evolution (LTE) and/or evolution of LTE systems. The evolutionof LTE systems includes LTE-advanced (LTE-A), LTE-A Pro, and/or 5G newradio (NR). The communication standard by the IEEE standardizationorganization includes a wireless local area network (WLAN) system suchas IEEE 802.11a/b/g/n/ac/ax. The above system uses various multipleaccess technologies such as orthogonal frequency division multipleaccess (OFDMA) and/or single carrier frequency division multiple access(SC-FDMA) for downlink (DL) and/or uplink (UL). For example, only OFDMAmay be used for DL and only SC-FDMA may be used for UL. Alternatively,OFDMA and SC-FDMA may be used for DL and/or UL.

In this document, the term “/” and “,” should be interpreted to indicate“and/or.” For instance, the expression “A/B” may mean “A and/or B.”Further, “A, B” may mean “A and/or B.” Further, “A/B/C” may mean “atleast one of A, B, and/or C.” Also, “A, B, C” may mean “at least one ofA, B, and/or C.”

Further, in the document, the term “or” should be interpreted toindicate “and/or.” For instance, the expression “A or B” may comprise 1)only A, 2) only B, and/or 3) both A and B. In other words, the term “or”in this document should be interpreted to indicate “additionally oralternatively.”

FIG. 1 shows examples of 5G usage scenarios to which the technicalfeatures of the present disclosure can be applied.

The 5G usage scenarios shown in FIG. 1 are only exemplary, and thetechnical features of the present disclosure can be applied to other 5Gusage scenarios which are not shown in FIG. 1.

Referring to FIG. 1, the three main requirements areas of 5G include (1)enhanced mobile broadband (eMBB) domain, (2) massive machine typecommunication (mMTC) area, and (3) ultra-reliable and low latencycommunications (URLLC) area. Some use cases may require multiple areasfor optimization and, other use cases may only focus on only one keyperformance indicator (KPI). 5G is to support these various use cases ina flexible and reliable way.

eMBB focuses on across-the-board enhancements to the data rate, latency,user density, capacity and coverage of mobile broadband access. The eMBBaims ˜10 Gbps of throughput. eMBB far surpasses basic mobile Internetaccess and covers rich interactive work and media and entertainmentapplications in cloud and/or augmented reality. Data is one of the keydrivers of 5G and may not be able to see dedicated voice services forthe first time in the 5G era. In 5G, the voice is expected to beprocessed as an application simply using the data connection provided bythe communication system. The main reason for the increased volume oftraffic is an increase in the size of the content and an increase in thenumber of applications requiring high data rates. Streaming services(audio and video), interactive video and mobile Internet connectivitywill become more common as more devices connect to the Internet. Many ofthese applications require always-on connectivity to push real-timeinformation and notifications to the user. Cloud storage andapplications are growing rapidly in mobile communication platforms,which can be applied to both work and entertainment. Cloud storage is aspecial use case that drives growth of uplink data rate. 5G is also usedfor remote tasks on the cloud and requires much lower end-to-end delayto maintain a good user experience when the tactile interface is used.In entertainment, for example, cloud games and video streaming areanother key factor that increases the demand for mobile broadbandcapabilities. Entertainment is essential in smartphones and tabletsanywhere, including high mobility environments such as trains, cars andairplanes. Another use case is augmented reality and informationretrieval for entertainment. Here, augmented reality requires very lowlatency and instantaneous data amount.

mMTC is designed to enable communication between devices that arelow-cost, massive in number and battery-driven, intended to supportapplications such as smart metering, logistics, and field and bodysensors. mMTC aims ˜10 years on battery and/or ˜1 million devices/km2.mMTC allows seamless integration of embedded sensors in all areas and isone of the most widely used 5G applications. Potentially by 2020,internet-of-things (IoT) devices are expected to reach 20.4 billion.Industrial IoT is one of the areas where 5G plays a key role in enablingsmart cities, asset tracking, smart utilities, agriculture, and securityinfrastructures.

URLLC will make it possible for devices and machines to communicate withultra-reliability, very low latency and high availability, making itideal for vehicular communication, industrial control, factoryautomation, remote surgery, smart grids and public safety applications.URLLC aims ˜1 ms of latency. URLLC includes new services that willchange the industry through links with ultra-reliability/low latency,such as remote control of key infrastructure and self-driving vehicles.The level of reliability and latency is essential for smart gridcontrol, industrial automation, robotics, drones control andcoordination.

Next, a plurality of use cases included in the triangle of FIG. 1 willbe described in more detail.

5G can complement fiber-to-the-home (FTTH) and cable-based broadband (orDOCSIS) as a means of delivering streams rated from hundreds of megabitsper second to gigabits per second. This high speed can be required todeliver TVs with resolutions of 4K or more (6K, 8K and above) as well asvirtual reality (VR) and augmented reality (AR). VR and AR applicationsinclude mostly immersive sporting events. Certain applications mayrequire special network settings. For example, in the case of a VR game,a game company may need to integrate a core server with an edge networkserver of a network operator to minimize delay.

Automotive is expected to become an important new driver for 5G, withmany use cases for mobile communications to vehicles. For example,entertainment for passengers demands high capacity and high mobilebroadband at the same time. This is because future users will continueto expect high-quality connections regardless of their location andspeed. Another use case in the automotive sector is an augmented realitydashboard. The driver can identify an object in the dark on top of whatis being viewed through the front window through the augmented realitydashboard. The augmented reality dashboard displays information thatwill inform the driver about the object's distance and movement. In thefuture, the wireless module enables communication between vehicles,information exchange between the vehicle and the supportinginfrastructure, and information exchange between the vehicle and otherconnected devices (e.g. devices accompanied by a pedestrian). The safetysystem allows the driver to guide the alternative course of action sothat he can drive more safely, thereby reducing the risk of accidents.The next step will be a remotely controlled vehicle or self-drivingvehicle. This requires a very reliable and very fast communicationbetween different self-driving vehicles and between vehicles andinfrastructure. In the future, a self-driving vehicle will perform alldriving activities, and the driver will focus only on traffic that thevehicle itself cannot identify. The technical requirements ofself-driving vehicles require ultra-low latency and high-speedreliability to increase traffic safety to a level not achievable byhumans.

Smart cities and smart homes, which are referred to as smart societies,will be embedded in high density wireless sensor networks. Thedistributed network of intelligent sensors will identify conditions forcost and energy-efficient maintenance of a city or house. A similarsetting can be performed for each home. Temperature sensors, windows andheating controllers, burglar alarms and appliances are all wirelesslyconnected. Many of these sensors typically require low data rate, lowpower and low cost. However, for example, real-time high-definition (HD)video may be required for certain types of devices for monitoring.

The consumption and distribution of energy, including heat or gas, ishighly dispersed, requiring automated control of distributed sensornetworks. The smart grid interconnects these sensors using digitalinformation and communication technologies to collect and act oninformation. This information can include supplier and consumerbehavior, allowing the smart grid to improve the distribution of fuel,such as electricity, in terms of efficiency, reliability, economy,production sustainability, and automated methods. The smart grid can beviewed as another sensor network with low latency.

The health sector has many applications that can benefit from mobilecommunications. Communication systems can support telemedicine toprovide clinical care in remote locations. This can help to reducebarriers to distance and improve access to health services that are notcontinuously available in distant rural areas. It is also used to savelives in critical care and emergency situations. Mobile communicationbased wireless sensor networks can provide remote monitoring and sensorsfor parameters such as heart rate and blood pressure.

Wireless and mobile communications are becoming increasingly importantin industrial applications. Wiring costs are high for installation andmaintenance. Thus, the possibility of replacing a cable with a wirelesslink that can be reconfigured is an attractive opportunity in manyindustries. However, achieving this requires that wireless connectionsoperate with similar delay, reliability, and capacity as cables and thattheir management is simplified. Low latency and very low errorprobabilities are new requirements that need to be connected to 5G.

Logistics and freight tracking are important use cases of mobilecommunications that enable tracking of inventory and packages anywhereusing location based information systems. Use cases of logistics andfreight tracking typically require low data rates, but require a largerange and reliable location information.

FIG. 2 shows an example of a wireless communication system to which thetechnical features of the present disclosure can be applied.

Referring to FIG. 2, the wireless communication system may include afirst device 210 and a second device 220.

The first device 210 includes a base station, a network node, atransmitting UE, a receiving UE, a wireless device, a wirelesscommunication device, a vehicle, a vehicle equipped with an autonomousdriving function, a connected car, a drone, an unmanned aerial vehicle(UAV), an artificial intelligence (AI) module, a robot, an AR device, aVR device, a mixed reality (MR) device, a hologram device, a publicsafety device, an MTC device, an IoT device, a medical device, afin-tech device (or, a financial device), a security device, aclimate/environmental device, a device related to 5G services, or adevice related to the fourth industrial revolution.

The second device 220 includes a base station, a network node, atransmitting UE, a receiving UE, a wireless device, a wirelesscommunication device, a vehicle, a vehicle equipped with an autonomousdriving function, a connected car, a drone, a UAV, an AI module, arobot, an AR device, a VR device, an MR device, a hologram device, apublic safety device, an MTC device, an IoT device, a medical device, afin-tech device (or, a financial device), a security device, aclimate/environmental device, a device related to 5G services, or adevice related to the fourth industrial revolution.

For example, the UE may include a mobile phone, a smart phone, a laptopcomputer, a digital broadcasting terminal, a personal digital assistant(PDA), a portable multimedia player (PMP), a navigation device, a slatepersonal computer (PC), a tablet PC, an ultrabook, a wearable device(e.g. a smartwatch, a smart glass, a head mounted display (HMD)). Forexample, the HMD may be a display device worn on the head. For example,the HMD may be used to implement AR, VR and/or MR.

For example, the drone may be a flying object that is flying by a radiocontrol signal without a person boarding it. For example, the VR devicemay include a device that implements an object or background in thevirtual world. For example, the AR device may include a device thatimplements connection of an object and/or a background of a virtualworld to an object and/or a background of the real world. For example,the MR device may include a device that implements fusion of an objectand/or a background of a virtual world to an object and/or a backgroundof the real world. For example, the hologram device may include a devicethat implements a 360-degree stereoscopic image by recording and playingstereoscopic information by utilizing a phenomenon of interference oflight generated by the two laser lights meeting with each other, calledholography. For example, the public safety device may include a videorelay device or a video device that can be worn by the user's body. Forexample, the MTC device and the IoT device may be a device that do notrequire direct human intervention or manipulation. For example, the MTCdevice and the IoT device may include a smart meter, a vending machine,a thermometer, a smart bulb, a door lock and/or various sensors. Forexample, the medical device may be a device used for the purpose ofdiagnosing, treating, alleviating, handling, or preventing a disease.For example, the medical device may be a device used for the purpose ofdiagnosing, treating, alleviating, or correcting an injury or disorder.For example, the medical device may be a device used for the purpose ofinspecting, replacing or modifying a structure or function. For example,the medical device may be a device used for the purpose of controllingpregnancy. For example, the medical device may include a treatmentdevice, a surgical device, an (in vitro) diagnostic device, a hearingaid and/or a procedural device, etc. For example, a security device maybe a device installed to prevent the risk that may occur and to maintainsafety. For example, the security device may include a camera, aclosed-circuit TV (CCTV), a recorder, or a black box. For example, thefin-tech device may be a device capable of providing financial servicessuch as mobile payment. For example, the fin-tech device may include apayment device or a point of sales (POS). For example, theclimate/environmental device may include a device for monitoring orpredicting the climate/environment.

The first device 210 may include at least one or more processors, suchas a processor 211, at least one memory, such as a memory 212, and atleast one transceiver, such as a transceiver 213. The processor 211 mayperform the functions, procedures, and/or methods of the presentdisclosure described below. The processor 211 may perform one or moreprotocols. For example, the processor 211 may perform one or more layersof the air interface protocol. The memory 212 is connected to theprocessor 211 and may store various types of information and/orinstructions. The transceiver 213 is connected to the processor 211 andmay be controlled to transmit and receive wireless signals.

The second device 220 may include at least one or more processors, suchas a processor 221, at least one memory, such as a memory 222, and atleast one transceiver, such as a transceiver 223. The processor 221 mayperform the functions, procedures, and/or methods of the presentdisclosure described below. The processor 221 may perform one or moreprotocols. For example, the processor 221 may perform one or more layersof the air interface protocol. The memory 222 is connected to theprocessor 221 and may store various types of information and/orinstructions. The transceiver 223 is connected to the processor 221 andmay be controlled to transmit and receive wireless signals.

The memory 212, 222 may be connected internally or externally to theprocessor 211, 221, or may be connected to other processors via avariety of technologies such as wired or wireless connections.

The first device 210 and/or the second device 220 may have more than oneantenna. For example, antenna 214 and/or antenna 224 may be configuredto transmit and receive wireless signals.

FIG. 3 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

Specifically, FIG. 3 shows a system architecture based on anevolved-UMTS terrestrial radio access network (E-UTRAN). Theaforementioned LTE is a part of an evolved-UTMS (e-UMTS) using theE-UTRAN.

Referring to FIG. 3, the wireless communication system includes one ormore user equipment (UE) 310, an E-UTRAN and an evolved packet core(EPC). The UE 310 refers to a communication equipment carried by a user.The UE 310 may be fixed or mobile. The UE 310 may be referred to asanother terminology, such as a mobile station (MS), a user terminal(UT), a subscriber station (SS), and a wireless device, etc.

The E-UTRAN consists of one or more evolved NodeB (eNB) 320. The eNB 320provides the E-UTRA user plane and control plane protocol terminationstowards the UE 10. The eNB 320 is generally a fixed station thatcommunicates with the UE 310. The eNB 320 hosts the functions, such asinter-cell radio resource management (RRM), radio bearer (RB) control,connection mobility control, radio admission control, measurementconfiguration/provision, dynamic resource allocation (scheduler), etc.The eNB 320 may be referred to as another terminology, such as a basestation (BS), a base transceiver system (BTS), an access point (AP),etc.

A downlink (DL) denotes communication from the eNB 320 to the UE 310. Anuplink (UL) denotes communication from the UE 310 to the eNB 320. Asidelink (SL) denotes communication between the UEs 310. In the DL, atransmitter may be a part of the eNB 320, and a receiver may be a partof the UE 310. In the UL, the transmitter may be a part of the UE 310,and the receiver may be a part of the eNB 320. In the SL, thetransmitter and receiver may be a part of the UE 310.

The EPC includes a mobility management entity (MME), a serving gateway(S-GW) and a packet data network (PDN) gateway (P-GW). The MME hosts thefunctions, such as non-access stratum (NAS) security, idle statemobility handling, evolved packet system (EPS) bearer control, etc. TheS-GW hosts the functions, such as mobility anchoring, etc. The S-GW is agateway having an E-UTRAN as an endpoint. For convenience, MME/S-GW 330will be referred to herein simply as a “gateway,” but it is understoodthat this entity includes both the MME and S-GW. The P-GW hosts thefunctions, such as UE Internet protocol (IP) address allocation, packetfiltering, etc. The P-GW is a gateway having a PDN as an endpoint. TheP-GW is connected to an external network.

The UE 310 is connected to the eNB 320 by means of the Uu interface. TheUEs 310 are interconnected with each other by means of the PC5interface. The eNBs 320 are interconnected with each other by means ofthe X2 interface. The eNBs 320 are also connected by means of the S1interface to the EPC, more specifically to the MME by means of theS1-MME interface and to the S-GW by means of the S1-U interface. The S1interface supports a many-to-many relation between MMEs/S-GWs and eNBs.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

Specifically, FIG. 4 shows a system architecture based on a 5G NR. Theentity used in the 5G NR (hereinafter, simply referred to as “NW”) mayabsorb some or all of the functions of the entities introduced in FIG. 3(e.g. eNB, MME, S-GW). The entity used in the NR may be identified bythe name “NG” for distinction from the LTE/LTE-A.

Referring to FIG. 4, the wireless communication system includes one ormore UE 410, a next-generation RAN (NG-RAN) and a 5th generation corenetwork (5GC). The NG-RAN consists of at least one NG-RAN node. TheNG-RAN node is an entity corresponding to the eNB 320 shown in FIG. 3.The NG-RAN node consists of at least one gNB 421 and/or at least oneng-eNB 422. The gNB 421 provides NR user plane and control planeprotocol terminations towards the UE 410. The ng-eNB 422 provides E-UTRAuser plane and control plane protocol terminations towards the UE 410.

The 5GC includes an access and mobility management function (AMF), auser plane function (UPF) and a session management function (SMF). TheAMF hosts the functions, such as NAS security, idle state mobilityhandling, etc. The AMF is an entity including the functions of theconventional MME. The UPF hosts the functions, such as mobilityanchoring, protocol data unit (PDU) handling. The UPF an entityincluding the functions of the conventional 5-GW. The SMF hosts thefunctions, such as UE IP address allocation, PDU session control.

The gNBs 421 and ng-eNBs 422 are interconnected with each other by meansof the Xn interface. The gNBs 421 and ng-eNBs 422 are also connected bymeans of the NG interfaces to the 5GC, more specifically to the AMF bymeans of the NG-C interface and to the UPF by means of the NG-Uinterface.

A protocol structure between network entities described above isdescribed. On the system of FIG. 3 and/or FIG. 4, layers of a radiointerface protocol between the UE and the network (e.g. NG-RAN and/orE-UTRAN) may be classified into a first layer (L1), a second layer (L2),and a third layer (L3) based on the lower three layers of the opensystem interconnection (OSI) model that is well-known in thecommunication system.

FIG. 5 shows a block diagram of a user plane protocol stack to which thetechnical features of the present disclosure can be applied. FIG. 6shows a block diagram of a control plane protocol stack to which thetechnical features of the present disclosure can be applied.

The user/control plane protocol stacks shown in FIG. 5 and FIG. 6 areused in NR. However, user/control plane protocol stacks shown in FIG. 5and FIG. 6 may be used in LTE/LTE-A without loss of generality, byreplacing gNB/AMF with eNB/MME.

Referring to FIG. 5 and FIG. 6, a physical (PHY) layer belonging to L1.The PHY layer offers information transfer services to media accesscontrol (MAC) sublayer and higher layers. The PHY layer offers to theMAC sublayer transport channels. Data between the MAC sublayer and thePHY layer is transferred via the transport channels. Between differentPHY layers, i.e., between a PHY layer of a transmission side and a PHYlayer of a reception side, data is transferred via the physicalchannels.

The MAC sublayer belongs to L2. The main services and functions of theMAC sublayer include mapping between logical channels and transportchannels, multiplexing/de-multiplexing of MAC service data units (SDUs)belonging to one or different logical channels into/from transportblocks (TB) delivered to/from the physical layer on transport channels,scheduling information reporting, error correction through hybridautomatic repeat request (HARQ), priority handling between UEs by meansof dynamic scheduling, priority handling between logical channels of oneUE by means of logical channel prioritization (LCP), etc. The MACsublayer offers to the radio link control (RLC) sublayer logicalchannels.

The RLC sublayer belong to L2. The RLC sublayer supports threetransmission modes, i.e. transparent mode (TM), unacknowledged mode(UM), and acknowledged mode (AM), in order to guarantee various qualityof services (QoS) required by radio bearers. The main services andfunctions of the RLC sublayer depend on the transmission mode. Forexample, the RLC sublayer provides transfer of upper layer PDUs for allthree modes, but provides error correction through ARQ for AM only. InLTE/LTE-A, the RLC sublayer provides concatenation, segmentation andreassembly of RLC SDUs (only for UM and AM data transfer) andre-segmentation of RLC data PDUs (only for AM data transfer). In NR, theRLC sublayer provides segmentation (only for AM and UM) andre-segmentation (only for AM) of RLC SDUs and reassembly of SDU (onlyfor AM and UM). That is, the NR does not support concatenation of RLCSDUs. The RLC sublayer offers to the packet data convergence protocol(PDCP) sublayer RLC channels.

The PDCP sublayer belong to L2. The main services and functions of thePDCP sublayer for the user plane include header compression anddecompression, transfer of user data, duplicate detection, PDCP PDUrouting, retransmission of PDCP SDUs, ciphering and deciphering, etc.The main services and functions of the PDCP sublayer for the controlplane include ciphering and integrity protection, transfer of controlplane data, etc.

The service data adaptation protocol (SDAP) sublayer belong to L2. TheSDAP sublayer is only defined in the user plane. The SDAP sublayer isonly defined for NR. The main services and functions of SDAP include,mapping between a QoS flow and a data radio bearer (DRB), and markingQoS flow ID (QFI) in both DL and UL packets. The SDAP sublayer offers to5GC QoS flows.

A radio resource control (RRC) layer belongs to L3. The RRC layer isonly defined in the control plane. The RRC layer controls radioresources between the UE and the network. To this end, the RRC layerexchanges RRC messages between the UE and the BS. The main services andfunctions of the RRC layer include broadcast of system informationrelated to AS and NAS, paging, establishment, maintenance and release ofan RRC connection between the UE and the network, security functionsincluding key management, establishment, configuration, maintenance andrelease of radio bearers, mobility functions, QoS management functions,UE measurement reporting and control of the reporting, NAS messagetransfer to/from NAS from/to UE.

In other words, the RRC layer controls logical channels, transportchannels, and physical channels in relation to the configuration,reconfiguration, and release of radio bearers. A radio bearer refers toa logical path provided by L1 (PHY layer) and L2 (MAC/RLC/PDCP/SDAPsublayer) for data transmission between a UE and a network. Setting theradio bearer means defining the characteristics of the radio protocollayer and the channel for providing a specific service, and setting eachspecific parameter and operation method. Radio bearer may be dividedinto signaling RB (SRB) and data RB (DRB). The SRB is used as a path fortransmitting RRC messages in the control plane, and the DRB is used as apath for transmitting user data in the user plane.

An RRC state indicates whether an RRC layer of the UE is logicallyconnected to an RRC layer of the E-UTRAN. In LTE/LTE-A, when the RRCconnection is established between the RRC layer of the UE and the RRClayer of the E-UTRAN, the UE is in the RRC connected state(RRC_CONNECTED). Otherwise, the UE is in the RRC idle state (RRC_IDLE).In NR, the RRC inactive state (RRC_INACTIVE) is additionally introduced.RRC_INACTIVE may be used for various purposes. For example, the massivemachine type communications (MMTC) UEs can be efficiently managed inRRC_INACTIVE. When a specific condition is satisfied, transition is madefrom one of the above three states to the other.

A predetermined operation may be performed according to the RRC state.In RRC_IDLE, public land mobile network (PLMN) selection, broadcast ofsystem information (SI), cell re-selection mobility, core network (CN)paging and discontinuous reception (DRX) configured by NAS may beperformed. The UE shall have been allocated an identifier (ID) whichuniquely identifies the UE in a tracking area. No RRC context stored inthe BS.

In RRC_CONNECTED, the UE has an RRC connection with the network (i.e.E-UTRAN/NG-RAN). Network-CN connection (both C/U-planes) is alsoestablished for UE. The UE AS context is stored in the network and theUE. The RAN knows the cell which the UE belongs to. The network cantransmit and/or receive data to/from UE. Network controlled mobilityincluding measurement is also performed.

Most of operations performed in RRC_IDLE may be performed inRRC_INACTIVE. But, instead of CN paging in RRC_IDLE, RAN paging isperformed in RRC_INACTIVE. In other words, in RRC_IDLE, paging formobile terminated (MT) data is initiated by core network and paging areais managed by core network. In RRC_INACTIVE, paging is initiated byNG-RAN, and RAN-based notification area (RNA) is managed by NG-RAN.Further, instead of DRX for CN paging configured by NAS in RRC_IDLE, DRXfor RAN paging is configured by NG-RAN in RRC_INACTIVE. Meanwhile, inRRC_INACTIVE, 5GC-NG-RAN connection (both C/U-planes) is established forUE, and the UE AS context is stored in NG-RAN and the UE. NG-RAN knowsthe RNA which the UE belongs to.

NAS layer is located at the top of the RRC layer. The NAS controlprotocol performs the functions, such as authentication, mobilitymanagement, security control.

The physical channels may be modulated according to OFDM processing andutilizes time and frequency as radio resources. The physical channelsconsist of a plurality of orthogonal frequency division multiplexing(OFDM) symbols in time domain and a plurality of subcarriers infrequency domain. One subframe consists of a plurality of OFDM symbolsin the time domain. A resource block is a resource allocation unit, andconsists of a plurality of OFDM symbols and a plurality of subcarriers.In addition, each subframe may use specific subcarriers of specific OFDMsymbols (e.g. first OFDM symbol) of the corresponding subframe for aphysical downlink control channel (PDCCH), i.e. L1/L2 control channel. Atransmission time interval (TTI) is a basic unit of time used by ascheduler for resource allocation. The TTI may be defined in units ofone or a plurality of slots, or may be defined in units of mini-slots.

The transport channels are classified according to how and with whatcharacteristics data are transferred over the radio interface. DLtransport channels include a broadcast channel (BCH) used fortransmitting system information, a downlink shared channel (DL-SCH) usedfor transmitting user traffic or control signals, and a paging channel(PCH) used for paging a UE. UL transport channels include an uplinkshared channel (UL-SCH) for transmitting user traffic or control signalsand a random access channel (RACH) normally used for initial access to acell.

Different kinds of data transfer services are offered by MAC sublayer.Each logical channel type is defined by what type of information istransferred. Logical channels are classified into two groups: controlchannels and traffic channels.

Control channels are used for the transfer of control plane informationonly. The control channels include a broadcast control channel (BCCH), apaging control channel (PCCH), a common control channel (CCCH) and adedicated control channel (DCCH). The BCCH is a DL channel forbroadcasting system control information. The PCCH is DL channel thattransfers paging information, system information change notifications.The CCCH is a channel for transmitting control information between UEsand network. This channel is used for UEs having no RRC connection withthe network. The DCCH is a point-to-point bi-directional channel thattransmits dedicated control information between a UE and the network.This channel is used by UEs having an RRC connection.

Traffic channels are used for the transfer of user plane informationonly. The traffic channels include a dedicated traffic channel (DTCH).The DTCH is a point-to-point channel, dedicated to one UE, for thetransfer of user information. The DTCH can exist in both UL and DL.

Regarding mapping between the logical channels and transport channels,in DL, BCCH can be mapped to BCH, BCCH can be mapped to DL-SCH, PCCH canbe mapped to PCH, CCCH can be mapped to DL-SCH, DCCH can be mapped toDL-SCH, and DTCH can be mapped to DL-SCH. In UL, CCCH can be mapped toUL-SCH, DCCH can be mapped to UL-SCH, and DTCH can be mapped to UL-SCH.

Hereinafter, Maintenance of Uplink Time Alignment, by a wireless device,will be described. It may be referred to as Section 5.2 of 3GPP TS36.321 V15.2.0 (2018-07).

The MAC entity has a configurable timer timeAlignmentTimer per TAG. ThetimeAlignmentTimer is used to control how long the MAC entity considersthe Serving Cells belonging to the associated TAG to be uplink timealigned.

The MAC entity shall:

1> when a Timing Advance Command MAC control element is received and ifa NTA has been stored or maintained with the indicated TAG:

2> apply the Timing Advance Command for the indicated TAG;

2> start or restart the timeAlignmentTimer associated with the indicatedTAG.

1> when a Timing Advance Command is received in a Random Access Responsemessage for a serving cell belonging to a TAG:

2> if the Random Access Preamble was not selected by the MAC entity:

3> apply the Timing Advance Command for this TAG;

3> start or restart the timeAlignmentTimer associated with this TAG.

2> else, if the timeAlignmentTimer associated with this TAG is notrunning:

3> apply the Timing Advance Command for this TAG;

3> start the timeAlignmentTimer associated with this TAG;

3> when the contention resolution is considered not successful, stoptimeAlignmentTimer associated with this TAG.

2> else:

3> ignore the received Timing Advance Command.

1> when the MAC entity is configured with rach-Skip or rach-SkipSCG:

2> apply timing advance value indicated by targetTA in rach-Skip orrach-SkipSCG for the pTAG;

2> start the timeAlignmentTimer associated with this TAG.

1> when a timeAlignmentTimer expires:

2> if the timeAlignmentTimer is associated with the pTAG:

3> flush all HARQ buffers for all serving cells;

3> notify RRC to release PUCCH/SPUCCH for all serving cells;

3> notify RRC to release SRS for all serving cells;

3> for NB-IoT, notify RRC to release all dedicated resources for SR;

3> clear any configured downlink assignments and uplink grants;

3> consider all running timeAlignmentTimers as expired;

2> else if the timeAlignmentTimer is associated with an sTAG, then forall Serving Cells belonging to this TAG:

3> flush all HARQ buffers;

3> notify RRC to release SRS;

3> notify RRC to release PUCCH/SPUCCH, if configured;

3> clear any configured downlink assignments and uplink grants.

When the MAC entity stops uplink transmissions for an SCell due to thefact that the maximum uplink transmission timing difference or themaximum uplink transmission timing difference the UE can handle betweenTAGS of any MAC entity of the UE is exceeded, the MAC entity considersthe timeAlignmentTimer associated with the SCell as expired.

The MAC entity shall not perform any uplink transmission on a ServingCell except the Random Access Preamble transmission when thetimeAlignmentTimer associated with the TAG to which this Serving Cellbelongs is not running. Furthermore, when the timeAlignmentTimerassociated with the pTAG is not running, the MAC entity shall notperform any uplink transmission on any Serving Cell except the RandomAccess Preamble transmission on the SpCell.

The MAC entity shall not perform any sidelink transmission which isperformed based on UL timing of the corresponding serving cell and anyassociated SCI transmissions when the corresponding timeAlignmentTimeris not running.

NOTE: A MAC entity stores or maintains NTA upon expiry of associatedtimeAlignmentTimer. The MAC entity applies a received Timing AdvanceCommand MAC control element and starts associated timeAlignmentTimeralso when the timeAlignmentTimer is not running.

Hereinafter, Semi-Persistent Scheduling, by a wireless device, will bedescribed. It may be referred to as Section 5.10 of 3GPP TS 36.321V15.2.0 (2018-07).

Multiple UL Semi-Persistent Scheduling configurations are supported perServing Cell. On one Serving Cell, multiple such configurations can beactive simultaneously only for the same TTI length. Multipleconfigurations can also be active simultaneously on different ServingCells.

When Semi-Persistent Scheduling is enabled by RRC:

1> Semi-Persistent Scheduling C-RNTI or UL Semi-Persistent SchedulingV-RNTI;

1> Uplink Semi-Persistent Scheduling interval semiPersistSchedIntervalULif short TTI in UL for the SpCell is not configured orsemiPersistSchedIntervalUL-sTTI in UL for the SpCell if short TTI isconfigured and number of empty transmissions before implicit releaseimplicitReleaseAfter, if Semi-Persistent Scheduling with Semi-PersistentScheduling C-RNTI is enabled for the uplink;

1> Uplink Semi-Persistent Scheduling interval semiPersistSchedIntervalULand number of empty transmissions before implicit releaseimplicitReleaseAfter for each SPS configuration, if Semi-PersistentScheduling with UL Semi-Persistent Scheduling V-RNTI is enabled for theuplink;

1> Whether twoIntervalsConfig is enabled or disabled for uplink, onlyfor TDD;

1> Downlink Semi-Persistent Scheduling intervalsemiPersistSchedIntervalDL if short TTI in DL for the SpCell is notconfigured or semiPersistSchedIntervalDL-sTTI if short TTI in DL for theSpCell is configured and number of configured HARQ processes forSemi-Persistent Scheduling numberOfConfSPS-Processes, if Semi-PersistentScheduling is enabled for the downlink;

1> sTTIStartTimeDl if short TTI in DL for the SpCell is configured andsTTIStartTimeUl if short TTI in UL for the SpCell is configured;

When Semi-Persistent Scheduling for uplink or downlink is disabled byRRC, the corresponding configured grant or configured assignment shallbe discarded.

Semi-Persistent Scheduling is not supported for RN communication withthe E-UTRAN in combination with an RN subframe configuration.

NOTE: When eIMTA is configured, if a configured uplink grant or aconfigured downlink assignment occurs on a subframe that can bereconfigured through eIMTA L1 signalling, then the UE behaviour is leftunspecified.

Hereinafter, Downlink and Uplink of Semi-Persistent Scheduling, by awireless device, will be described.

After a Semi-Persistent downlink assignment is configured, the MACentity shall consider sequentially that the Nth assignment occurs in theTTI for which:

1> subframe SPS is used:

2> (10*SFN+subframe)=[(10*SFNstart time+subframestarttime)+N*semiPersistSchedIntervalDL] modulo 10240.

1> slot or subslot SPS is used:

2>(10*SFN*sTTI_Number_Per_Subframe+subframe*sTTI_Number_Per_Subframe+sTTI_number)=[(10*SFNstarttime*sTTI_Number_Per_Subframe+subframestarttime*sTTI_Number_Per_Subframe+sTTIStartTimeDl)+N*semiPersistSchedIntervalDL-sTTI]modulo (10240*sTTI_Number_Per_Subframe).

Where SFNstart time, subframestart time and sTTIStartTimeDl are the SFN,subframe and sTTI_number, respectively, at the time the configureddownlink assignment were (re-)initialised. The sTTI_Number_Per_Subframeis 6 when subslot TTI is configured and 2 when slot TTI is configuredfor short TTI operation. sTTI_number refers to the index of the shortTTI, i.e., index of subslot or slot within the subframe.

For BL UEs or UEs in enhanced coverage SFNstart time and subframestarttime refer to SFN and subframe of the first transmission of PDSCH whereconfigured downlink assignment was (re-)initialized.

After a Semi-Persistent Scheduling uplink grant is configured, the MACentity shall:

1> if twoIntervalsConfig is enabled by upper layer:

2> set the Subframe_Offset.

1> else:

2> set Subframe_Offset to 0.

1> consider sequentially that the Nth grant occurs in the TTI for which:

2> subframe SPS is used:

3> (10*SFN+subframe)=[(10*SFNstart time+subframestarttime)+N*semiPersistSchedIntervalUL+Subframe_Offset*(N modulo 2)] modulo10240.

2> slot or subslot SPS is used:

3>(10*SFN*sTTI_Number_Per_Subframe+subframe*sTTI_Number_Per_Subframe+sTTI_number)=[(10*SFNstarttime*sTTI_Number_Per_Subframe+subframestarttime*sTTI_Number_Per_Subframe+sTTlStartTimeUl)+N*semiPersistSchedIntervalUL-sTTI+Subframe_Offset*(Nmodulo 2)*sTTI_Number_Per_Subframe] modulo(10240*sTTI_Number_Per_Subframe).

Where SFNstart time, subframestart time and sTTlStartTimeUl are the SFN,subframe and sTTI_number, respectively, at the time the configureduplink grant were (re-)initialised. The sTTI_Number_Per_Subframe is 6when subslot TTI is configured and 2 when slot TTI is configured forshort TTI operation. sTTI_number refers to the index of the short TTI,i.e., index of subslot or slot within the subframe.

Except for NB-IoT, for TDD, the MAC entity is configured withsemiPersistSchedIntervalUL shorter than 10 subframes, the Nth grantshall be ignored if it occurs in a downlink subframe or a specialsubframe.

Except for NB-IoT, if the MAC entity is not configured withskipUplinkTxSPS, the MAC entity shall clear the configured uplink grantimmediately after implicitReleaseAfter number of consecutive new MACPDUs each containing zero MAC SDUs have been provided by theMultiplexing and Assembly entity, on the Semi-Persistent Schedulingresource.

If SPS confirmation has been triggered and not cancelled:

1> if the MAC entity has UL resources allocated for new transmission forthis TTI:

2> instruct the Multiplexing and Assembly procedure to generate an SPSconfirmation MAC Control Element;

2> cancel the triggered SPS confirmation.

The MAC entity shall clear the configured uplink grant immediately afterfirst transmission of SPS confirmation MAC Control Element triggered bythe SPS release.

NOTE: Retransmissions for Semi-Persistent Scheduling can continue afterclearing the configured uplink grant.

For NB-IoT UEs, BL UEs or UEs in enhanced coverage SFNstart time andsubframestart time refer to SFN and subframe of the first transmissionof PUSCH where configured uplink grant was (re-)initialized.

In the event of a resource conflict between multiple UL SPSconfigurations configured with Uplink Semi-Persistent Scheduling V-RNTI,the UE behavior is undefined.

For NB-IoT UEs, a configured uplink grant shall be used only for BSRtransmission and uplink skip mechanism is implicitly supported.

Hereinafter, uplink transmission without dynamic scheduling, by awireless device, will be described. It may be referred to as Section5.8.2 of 3GPP TS 38.321 V15.3.0 (2018-09).

There are two types of transmission without dynamic grant:

-   -   configured grant Type 1 where an uplink grant is provided by        RRC, and stored as configured uplink grant;    -   configured grant Type 2 where an uplink grant is provided by        PDCCH, and stored or cleared as configured uplink grant based on        L1 signalling indicating configured uplink grant activation or        deactivation.

Type 1 and Type 2 are configured by RRC per Serving Cell and per BWP.Multiple configurations can be active simultaneously only on differentServing Cells. For Type 2, activation and deactivation are independentamong the Serving Cells. For the same Serving Cell, the MAC entity isconfigured with either Type 1 or Type 2.

RRC configures the following parameters when the configured grant Type 1is configured:

-   -   cs-RNTI: CS-RNTI for retransmission;    -   periodicity: periodicity of the configured grant Type 1;    -   timeDomainOffset: Offset of a resource with respect to SFN=0 in        time domain;    -   timeDomainAllocation: Allocation of configured uplink grant in        time domain which contains startSymbolAndLength (i.e. SLIV);    -   nrofHARQ-Processes: the number of HARQ processes for configured        grant.

RRC configures the following parameters when the configured grant Type 2is configured:

-   -   cs-RNTI: CS-RNTI for activation, deactivation, and        retransmission;    -   periodicity: periodicity of the configured grant Type 2;    -   nrofHARQ-Processes: the number of HARQ processes for configured        grant.

Upon configuration of a configured grant Type 1 for a Serving Cell byupper layers, the MAC entity shall:

1> store the uplink grant provided by upper layers as a configureduplink grant for the indicated Serving Cell;

1> initialise or re-initialise the configured uplink grant to start inthe symbol according to timeDomainOffset and S (derived from SLIV), andto reoccur with periodicity.

When a configured uplink grant is released by upper layers, all thecorresponding configurations shall be released and all correspondinguplink grants shall be cleared.

The MAC entity shall:

1> if the configured uplink grant confirmation has been triggered andnot cancelled; and

1> if the MAC entity has UL resources allocated for new transmission:

2> instruct the Multiplexing and Assembly procedure to generate anConfigured Grant Confirmation MAC CE;

2> cancel the triggered configured uplink grant confirmation.

For a configured grant Type 2, the MAC entity shall clear the configureduplink grant immediately after first transmission of Configured GrantConfirmation MAC CE triggered by the configured uplink grantdeactivation.

Retransmissions except for repetition of configured uplink grants useuplink grants addressed to CS-RNTI.

The RRC inactive state is described in detail. The following descriptionof the RRC inactive state will be described by taking NR as an example,but it can be applied to LTE-A without loss of generality. For example,in the following description, NG-RAN node/gNB may be replaced with eNBand/or more generally BS, and AMF may be replaced with MME.

The RRC inactive state applies to NG-RAN node. The AMF, based on networkconfiguration, may provide RRC inactive assistance information to theNG-RAN node, to assist the NG-RAN's decision whether the UE can be sentto RRC inactive state.

The RRC inactive assistance information includes at least one of thefollowings.

-   -   UE specific DRX values    -   The registration area provided to the UE    -   Periodic registration update timer    -   If the AMF has enabled mobile initiated connection only (MICO)        mode for the UE, an indication that the UE is in MICO mode.    -   Information from the UE permanent identifier that allows the        NG-RAN node to calculate the UE's RAN paging occasions.

The RRC inactive assistance information mentioned above is provided bythe AMF during N2 activation with the (new) serving NG-RAN node (i.e.during registration, service request, handover) to assist the NG-RANnode's decision whether the UE can be sent to RRC inactive state. RRCinactive state is part of RRC state machine, and it is up to the NG-RANnode to determine the conditions to enter RRC inactive state. If any ofthe parameters included in the RRC inactive assistance informationchanges as the result of NAS procedure, the AMF shall update the RRCinactive assistance information to the NG-RAN node.

When the UE is in connection management connected state (CM-CONNECTED),if the AMF has provided RRC inactive assistance information, the NG-RANnode may decide to move a UE to CM-CONNECTED with RRC inactive state.

The state of the N2 and N3 reference points are not changed by the UEentering CM-CONNECTED with RRC inactive state. A UE in RRC inactivestate is aware of the RAN notification area.

The 5GC network is not aware of the UE transitions between CM-CONNECTEDwith RRC_CONNECTED and CM-CONNECTED with RRC inactive state, unless the5GC network is notified via N2 notification procedure.

At transition into CM-CONNECTED with RRC inactive state, the NG-RAN nodeconfigures the UE with a periodic RAN notification area update timertaking into account the value of the periodic registration update timervalue indicated in the RRC inactive assistance information, and uses aguard timer with a value longer than the RAN notification area updatetimer value provided to the UE.

If the periodic RAN notification area update guard timer expires inNG-RAN node, the NG-RAN node shall initiate access network (AN) releaseprocedure.

When the UE is in CM-CONNECTED with RRC inactive state, the UE performsPLMN selection procedures for connection management idle state(CM-IDLE).

When the UE is CM-CONNECTED with RRC inactive state, the UE may resumethe RRC connection due to at least one of the followings.

-   -   UL data pending    -   Mobile originated (MO) NAS signaling procedure    -   As a response to RAN paging    -   Notifying the network that it has left the RAN notification area    -   Upon periodic RAN update timer expiration.

If the UE resumes the connection in a different NG-RAN node within thesame PLMN, the UE AS context is retrieved from the old NG-RAN node and aprocedure is triggered towards the CN.

If the RAN paging procedure is not successful in establishing contactwith the UE, the procedure shall be handled by the network as follows.

-   -   If NG-RAN node has at least one pending NAS PDU for        transmission, the NG-RAN node shall initiate the AN release        procedure to move the UE CM state in the AMF to CM-IDLE and        indicate to the AMF the NAS non-delivery.    -   If NG-RAN node has only pending user plane data for        transmission, the NG-RAN node may keep the N2 connection active        or initiate the AN release procedure based on local        configuration in NG-RAN node.

The user plane data which triggers the RAN paging can be lost, e.g. inthe case of RAN paging failure.

If a UE in CM-CONNECTED with RRC inactive state performs cell selectionto GERAN/UTRAN/E-UTRAN, it shall follow idle mode procedures of theselected RAT.

In addition, a UE in CM-CONNECTED state with RRC inactive state shallenter CM-IDLE and initiates the NAS signaling recovery in at least oneof the following cases.

-   -   If RRC resume procedure fails;    -   If the UE receives core network paging;    -   If the periodic RAN notification area update timer expires and        the UE cannot successfully resume the RRC connection;    -   In any other failure scenario that cannot be resolved in RRC        inactive state and requires the UE to move to CM-IDLE.

When the UE is in CM-CONNECTED with RRC inactive state, if NG-RAN nodehas received location reporting control message from AMF with thereporting type indicating single stand-alone report, the NG-RAN nodeshall perform RAN paging before reporting the location to AMF.

When the UE is in CM-CONNECTED with RRC inactive state, if NG-RAN nodehas received location reporting control message from AMF with thereporting type indicating continuously reporting whenever the UE changescell, the NG-RAN node shall send a location report message to AMFincluding UE's last known location with time stamp.

When the UE is CM-CONNECTED with RRC inactive state, if the AMF receivesNudm_UEContextManagement_DeregistrationNotification from user datamanagement (UDM), the AMF shall initiate AN release procedure.

When UE is in CM-CONNECTED with RRC inactive state, if NG-RAN node hasreceived location reporting control message from AMF with the reportingtype of the area of interest based reporting, the NG-RAN node shall senda location report message to AMF including UE presence in the area ofinterest (i.e. IN, OUT, or UNKNOWN) and the UE's last known locationwith time stamp.

FIG. 7 shows an example of a connection resume procedure to which thetechnical features of the present disclosure can be applied. Theconnection resume procedure is used by the UE to perform RRC inactive toRRC connected state transition.

In step S700, while the UE is in RRC_INACTIVE, the UE transmits an RRCmessage to the NG-RAN node to initiate the transition from RRC_INACTIVEto RRC_CONNECTED. The UE provides its resume ID needed by the NG-RANnode to access the UE's stored context. The RRC message may beRRCConnectionResumeRequest message which will be described in detailbelow.

In step S702, the NG-RAN node may conditionally perform UE contextretrieval. The UE context retrieval is performed when the UE contextassociated with the UE attempting to resume its connection is notlocally available at the accessed NG-RAN node.

In step S704, the NG-RAN node may conditionally perform N2 path switchprocedure towards the serving AMF. If the target NG-RAN node isdifferent from the old NG-RAN node, the serving NG-RAN node initiates N2path switch procedure and including Xn data forwarding. The NG-RAN nodesends UE notification message to report that the UE is in RRC_CONNECTEDif the AMF requested N2 notification to the NG-RAN node.

In step S706, the NG-RAN node transmits an RRC message to the UE toconfirm to the UE that the UE has entered RRC_CONNECTED. The RRC messageincludes resume ID of the UE.

The RRC connection release is described in detail. It may be referred toas Section 5.3 of 3GPP TS 38.331 V15.3.0 (2018-09).

The purpose of the RRC connection release procedure is:

1> to release the RRC connection, which includes the release of theestablished radio bearers as well as all radio resources; or

1> to suspend the RRC connection, which includes the suspension of theestablished radio bearers.

The network initiates the RRC connection release procedure to transit aUE in RRC_CONNECTED to RRC_IDLE; or to transit a UE in RRC_CONNECTED toRRC_INACTIVE; or to transit a UE in RRC_INACTIVE back to RRC_INACTIVEwhen the UE tries to resume; or to transit a UE in RRC_INACTIVE toRRC_IDLE when the UE tries to resume. The procedure can also be used torelease and redirect a UE to another frequency.

UE actions upon going to RRC_IDLE is described in detail.

UE shall:

1> reset MAC;

1> stop all timers that are running except T320 and T325;

1> discard any stored AS context, fullI-RNTI, shortI-RNTI-Value,ran-PagingCycle and ran-NotificationAreaInfo;

1> discard the AS security context including the KRRCenc key, theKRRCint, the KUPint key and the KUPenc key, if stored;

1> release all radio resources, including release of the RLC entity, theMAC configuration and the associated PDCP entity and SDAP for allestablished RBs;

1> indicate the release of the RRC connection to upper layers togetherwith the release cause;

1> enter RRC_IDLE and perform procedures, except if going to RRC_IDLEwas triggered by reception of the MobilityFromNRCommand message or byselecting an inter-RAT cell while T311 was running.

A wireless device may transmit data in RRC_IDLE state or RRC_INACTIVEstate with a network. For example, a wireless device may be configuredwith configured grant to transmit user data in RRC_IDLE state orRRC_INACTIVE state. However, when the configured grant is not validand/or uplink timing is not aligned with the network, a wireless devicecould not use the configured grant to transmit user data in RRC_IDLEstate or RRC_INACTIVE state. Therefore, a method for entering aconnected state with the network for continuing transmission in wirelesscommunication system is required.

Hereinafter, a method and a wireless device for entering a connectedstate with the network to continuing data transmission, according tosome embodiments of the present disclosure, will be described withreference to following drawings.

The following drawings are created to explain specific embodiments ofthe present disclosure. The names of the specific devices or the namesof the specific signals/messages/fields shown in the drawings areprovided by way of example, and thus the technical features of thepresent disclosure are not limited to the specific names used in thefollowing drawings.

FIG. 8 shows an example of a method for entering a connected state witha network for continuing transmission, according to some embodiments ofthe present disclosure. More specifically, FIG. 8 shows an example of anembodiment of the present disclosure on perspective of a wirelessdevice.

In step 801, a wireless device may start or restart a Time AlignmentTimer (TAT). A wireless device may have a configurable time alignmenttimer (TAT) per timing advance group (TAG), wherein a TAG may includeone or more serving cells with the same uplink timing advancing (TA) anddownlink timing reference cell.

For example, a wireless device may start or restart a TAT when a TimingAdvance Command (TAC) MAC control element (CE) is received. When a TACindicates a specific TAG, a wireless device may start or restart a TATassociated with the specific TAG. For other example, a wireless devicemay start or restart a TAT when a TAC is received in a Random AccessResponse message for a serving cell belonging to a TAG. For anotherexample, when a MAC entity of a wireless device is configured withrach-skip or rach-skipSCG for primary timing advance group (pTAG), suchas PCell, the wireless device may start a TAT associated with the TAG.

According to some embodiments of the present disclosure, a wirelessdevice may start or restart a TAT while in RRC_CONNECTED. The wirelessdevice may continue running TAT after leaving RRC_CONNECTED.

In step 802, a wireless device may receive configuration of a configuredgrant upon leaving RRC_CONNECTED. A wireless device may receiveconfiguration of a configured grant applicable to a validity area with avalidity timer upon leaving RRC_CONNECTED. The configured grant may be aresource of a Semi-Persistent Scheduling (SPS) configuration. Thevalidity area consists of one or more cells.

According to some embodiments of the present disclosure, theconfiguration of the configured grant may include a maximum amount ofdata (or maximum data rate) supported by the configured grant. Theconfiguration of the configured grant may include a wireless deviceIdentity (for example, a UE Identity), such as a SPS-I-RNTI, which isused by the wireless device when the wireless device performs uplinktransmission with the configured grant or downlink reception while inRRC_IDLE or RRC_INACTIVE.

In step 803, a wireless device may select a cell belonging to thevalidity area and camp on the selected cell. A wireless device mayselect a cell and camp on the selected cell, being in RRC_IDLE orRRC_INACTIVE.

In step 804, a wireless device may initiate uplink transmission of a RRCRequest message to enter RRC_CONNECTED. A wireless device may performrandom access procedure to send the RRC Request message.

A wireless device may initiate uplink transmission of the RRC Requestmessage when the Timer Alignment Timer (TAT) is expired. A wirelessdevice may initiate uplink transmission of the RRC Request message whenthe Timer Alignment Timer (TAT) is expired and data becomes available.

A wireless device may initiate uplink transmission of the RRC Requestmessage when the validity timer associated with the configured grantexpires. A wireless device may initiate uplink transmission of the RRCRequest message when the validity timer associated with the configuredgrant expires.

A wireless device may initiate uplink transmission of the RRC Requestmessage when the wireless device leaves the validity area associatedwith the configured grant. A wireless device may initiate uplinktransmission of the RRC Request message when the wireless device leavesthe validity area associated with the configured grant and data becomesavailable.

A wireless device may initiate uplink transmission of the RRC Requestmessage when data becomes available for a logical channel not mapped toSPS configuration.

A wireless device may initiate uplink transmission of the RRC Requestmessage when data becomes available and the amount of data available fortransmission is beyond the maximum amount of data. A wireless device mayinitiate uplink transmission of the RRC Request message when databecomes available and the amount of data available for transmission isbeyond the maximum data rate.

FIG. 9 shows a flow chart of an example of a method for entering aconnected state with a network for continuing transmission, according tosome embodiments of the present disclosure. More specifically, FIG. 9shows an example of an embodiment of the present disclosure onperspective of a network system. The description of the same parts asthose described above will be simplified or omitted.

In step 901, a wireless device may receive configuration for RRC setupfrom a network (for example, an eNB or a gNB).

In step 902, a wireless device may enter RRC_CONNECTED and EMM_CONNECTEDat a serving cell.

In step 903, a wireless device may receive configuration for SecurityMode Activation from a network. The wireless device may perform SecurityMode Activation to activate AS security.

In step 904, a wireless device may receive RRC ConnectionReconfiguration from the network to configure SPS configuration withSPS-I-RNTI. The SPS-I-RNTI may be used for data transmission inRRC_IDLE. The wireless device may receive SPS configuration via systeminformation regardless of RRC state.

According to some embodiments of the present disclosure, a wirelessdevice may start or restart TAT while in RRC_CONNECTED. A wirelessdevice may continue running TAT after leaving RRC_CONNECTED.

According to some embodiments of the present disclosure, a SPSconfiguration may include uplink and/or downlink SPS resources as uplinkand/or downlink configured grants, PRB or narrowband index. A SPSconfiguration may include a validity area, a validity timer, validlogical channels, maximum amount of data, or maximum data rate supportedby the configured grant. A SPS configuration may include a wirelessdevice Identity (for example, a UE Identity) such as a SPS-I-RNTI, whichis used by the wireless device when the wireless device performs uplinktransmission with the configured grant. The SPS configured grant may bevalid in the validity area consisting of one or more cells including theserving cell.

The SPS configuration or the SPS configured grant may be valid in theconfigured PRB or narrowband while a wireless device is in RRC_IDLE orRRC_INACTEVE. RRC Release, Paging, MAC Control Element or PDCCH receivedin RRC_IDLE or RRC_INACTIVE could indicate SPS activation with a PRBindex or a narrowband index for a particular SPS configured grant. Uponreceiving such SPS activation with a PRB index or a narrowband index, awireless device in RRC_IDLE or RRC_INACTIVE may consider the SPSconfigured grant or the SPS configuration as activated on the PRB or thenarrowband indicated by the index.

The SPS configured grant may be valid while a validity timer is running.The validity timer could be a time Alignment Timer (TAT) or anothertimer. The validity timer may be configured for each configured grant. Awireless device may start or restart the validity timer (e.g. TAT) whenthe SPS configured grant is received. A wireless device may start orrestart the validity timer when a wireless device leaves RRC_CONNECTED.A wireless device may start or restart the validity timer when TimingAdvance Command is received, e.g. via MAC Control Element, Random AccessResponse, RRC Release message, or Paging message in RRC_IDLE orRRC_INACTIVE after leaving RRC_CONNECTED. The network may periodicallysend Timing Advance Command to the wireless device in RRC_IDLE orRRC_INACTIVE, e.g. by paging message in Paging Occasion of the wirelessdevice or MAC Control Element via DL SPS configured grant.

According to some embodiments of the present disclosure, the SPSconfigured grant may be valid only for configured valid logicalchannels. When a wireless device transmits data from the valid logicalchannel, the wireless device could use the SPS configured grant totransmit data.

In step 905, a wireless device may receive a RRC Release message from anetwork. The RRC Release message may include Suspend indication. The RRCRelease message may include command to pre-allocated resource, such asconfigured grant or SPS.

In step 906, a wireless device may leave RRC_CONNECTED state. When awireless device receives RRC Release message or RRC Release Indication(e.g. via PDCCH or MAC Control Element), the wireless device may leaveRRC_CONNETED. The wireless device may enter to RRC_IDLE. When a wirelessdevice receives a RRC Release message with a suspend indication, thewireless device may leave RRC_CONNETED. The wireless device may enter toRRC_INACTIVE. In RRC_IDLE or RRC_INACTIVE, a wireless device maytransmit user data via the configured grant.

In step 907, a wireless device may have data which becomes available fortransmitting to a network. A data may become available for uplinktransmission.

In step 908, a wireless device may transmit a MAC PDU to a network. Thewireless device may transmit a MAC PDU to a Core Network through an eNBor a gNB.

If RRC Release message (or a RRC Release message with a suspendindication) indicates uplink SPS activation for a particular SPSconfigured grant and if data becomes available for uplink transmissionin RRC_IDLE or RRC_ACTIVE, a wireless device may construct a MAC PDUincluding SPS Confirmation MAC Control Element with user data. The SPSConfirmation MAC CE may indicate that which SPS configured grant(s) isactivated or deactivated.

According to some embodiments of the present disclosure, a wirelessdevice may periodically transmit SPS Confirmation MAC CE to inform thenetwork that which SPS configured grant(s) is currently activated ordeactivated.

According to some embodiments of the present disclosure, In RRC_IDLEstate or RRC_INACTIVE state, a wireless device may perform cellreselection. If a wireless device performs cell reselection and camps onthe selected cell belonging to the validity area, a wireless device maysend SPS confirmation to a network to inform the network that which SPSconfigured grant(s) is currently activated or deactivated.

A wireless device in in RRC_IDLE or RRC_INACTIVE may perform uplinktransmissions by using the SPS configured grant. SPS configured grantcould be either contention based or contention free.

A wireless device in RRC_IDLE or RRC_INACTIVE should transmit data withan ID of the wireless device, such as SPS-I-RNTI or S-TMSI, incontention based SPS configured grant. A wireless device in RRC_IDLE orRRC_INACITVE may include an ID of the wireless device in a RRC messageor a MAC CE to be transmitted from uplink.

According to some embodiments of the present disclosure, beforetransmitting a MAC PDU by using contention based configured grant, awireless device in RRC_IDLE or RRC_INACTIVE may perform Access BarringCheck to determine whether or not to perform transmission of the MAC PDUvia the SPS configured grant based on barring information received fromsystem information. If access attempt is allowed as the result of AccessBarring Check, the wireless device may perform transmission of the MACPDU.

The network may indicate to a wireless device whether the SPS configuredgrant or the SPS configuration requires Access Barring Check. Thus, ifindicated, MAC of the wireless device may request RRC of the wirelessdevice to perform Access Barring Check before transmission of the MACPDU via the SPS configured grant. Then, RRC of the wireless device mayinform MAC of the wireless device about the result of the Access BarringCheck. If access attempt is allowed as the result of Access BarringCheck, MAC of the wireless device may perform transmission of the MACPDU.

According to some embodiments of the present disclosure, a wirelessdevice in RRC_IDLE or RRC_INACTIVE should transmit a MAC PDU with ID ofthe wireless device, such as SPS-I-RNTI or S-TMSI, in contention basedSPS configured grant. MAC entity of the wireless device may considertransmission of the MAC PDU as successful after contention resolutionmessage as well as positive HARQ feedback is received in downlink.

According to some embodiments of the present disclosure, a wirelessdevice in RRC_IDLE or RRC_INACTIVE could transmit data without ID of thewireless device in contention free SPS configured grant. A wirelessdevice may not need to perform Access Barring Check before transmittingMAC PDU by using contention free SPS configured grant. In this case, MACentity of the wireless device may consider transmission of the MAC PDUas successful after positive HARQ feedback is received in downlinkwithout contention resolution message.

According to some embodiment of the present disclosure, when a wirelessdevice enters RRC_IDLE (or RRC_INACTIVE) by receiving a RRC Releasemessage (or a RRC Release message with a suspend indication), the RRCRelease message (or the RRC Release message with a suspend indication)may indicate downlink SPS activation for a particular SPS configuredgrant. A wireless device may activate the downlink SPS configured grant.When data becomes available for downlink transmission in RRC_IDLE (orRRC_INACTIVE), the network may send user data by using the DL SPSconfigured grant. The network may indicates to the wireless device thatthe DL SPS is deactivated by sending Paging, MAC Control Element orPDCCH to the wireless device in RRC_IDLE (or RRC_INACTIVE). Then, thewireless device may transmit DL data via the SPS configured grant.

According to some embodiment of the present disclosure, when a wirelessdevice enters RRC_IDLE (or RRC_INACTIVE) by receiving a RRC Releasemessage (or a RRC Release message with a suspend indication), the RRCRelease message (or the RRC Release message with a suspend indication)may indicate downlink SPS deactivation for a particular SPS configuredgrant. Otherwise, the network may indicate to the wireless device thatthe DL SPS is deactivated by sending Paging, MAC Control Element orPDCCH to the wireless device in RRC_IDLE (or RRC_INACTIVE). In thiscase, the network may indicate to the wireless device that the DL SPS isactivated by sending Paging, MAC Control Element or PDCCH to thewireless device in RRC_IDLE (or RRC_INACTIVE). Then, the wireless devicemay transmit DL data via the SPS configured grant.

In step 909, a validity timer (e.g. a TAT) of a wireless device may beexpired or the wireless device may leave the validity area.

In step 910, data in a wireless device becomes available for uplinktransmission.

When the validity timer (e.g. a TAT) has been expired and/or when thedata becomes available, a wireless device may initiate Random Accessprocedure to perform RRC Connection Establishment procedure.

When the wireless device leaves the validity area and/or when the databecomes available, a wireless device may initiate Random Accessprocedure to perform RRC Connection Establishment procedure.

According to some embodiments of the present disclosure, when databecomes available for a logical channel which is not mapped to the SPSconfiguration or the SPS configured grant, a wireless device mayinitiate Random Access procedure to perform RRC Connection Establishmentprocedure.

According to some embodiments of the present disclosure, when databecomes available and the amount of data available for transmission isbeyond the maximum amount of data (or the maximum data rate), a wirelessdevice may initiate Random Access procedure to perform RRC ConnectionEstablishment procedure.

In step 911, a wireless device may transmit RACH preamble with a RAPID.A wireless device may deactivates the corresponding SPS configured grantor suspend the SPS configuration or release the SPS configuration. TheRAPID may be associated with the SPS configuration or the SPS configuredgrant.

In step 912, a wireless device may receive a Random Access Response(RAR) from a network. The network sends Random Access Response (RAR)message, in response to the RACH preamble, to the wireless device.

According to some embodiments of the present disclosure, the RAR messagemay include RAPID, Time Advance command, and SPS-I-RNTI. The RAR messagemay indicate that which type of message should be sent by a wirelessdevice (e.g. EarlyDataRequest, RRCConnectionRequest, orRRCResumeRequest). The RAR message may indicate that which procedureshould be triggered by the wireless device (e.g. EDT, RRC ConnectionEstablishment or RRC Resume procedure).

In step 913, a wireless device may transmit RRCConnectionRequest messageto a network. The wireless device may transmit RRCConnectionRequestmessage, based on the RAR message.

According to some embodiments of the present disclosure, a wirelessdevice may transmit RRCConnectionRequest message with user data to anetwork, for example an eNB or a gNB.

In step 914, an eNB or a gNB may transmit the user data received fromthe wireless device to a core network.

In step 915 a wireless device may receive RRCSetup message from anetwork. The RRCSetup message may include SPS reconfiguration and newSPS-I-RNTI

According to some embodiment of the present disclosure, a wirelessdevice may receive SPS reconfiguration and new SPS-I-RNTI, uponreceiving RRCSetup message. When a wireless device enters RRC_CONNECTEDafter receiving RRCSetup, the wireless device may transmit user datapossibly with RRC Connection Setup Complete.

According to an embodiment of the present disclosure described above,when data becomes available and if the configured grant cannot be usedand/or uplink timing is not aligned with the network, the UE cantransmit RRC request message to the network in order to enterRRC_CONNECTED from RRC_IDLE or RRC_INACTIVE. After enteringRRC_CONNECTED, the UE can align UL timing with the network and/or SPSconfiguration can be reconfigured. Therefore, the UE can continue datatransmission.

FIG. 10 shows a method for entering a connected state with a network forcontinuing data transmission, according to some embodiments of thepresent disclosure. The description of the same parts as those describedabove will be simplified or omitted.

In step 1001, a wireless device may start or restart a Time AlignmentTimer (TAT). For example, a wireless device may start or restart a TATupon receiving a Timing Advance Command (TAC) MAC control element (CE).For other example, a wireless device may start or restart a TAT uponreceiving a TAC in a Random Access Response message for a serving cellbelonging to a TAG.

According to some embodiments of the present disclosure, a wirelessdevice may start or restart a TAT in a connected state (e.g. RRCCONNECTED state) with a network. For example, a wireless device mayrestart the TAT, and continue running the TAT after leaving theconnected state. A wireless device may not restart the TAT upon leavingthe connected state.

According to some embodiments of the present disclosure, a wirelessdevice may restart a TAT when the wireless device enters to RRC INACTIVEstate or RRC IDLE state from RRC CONNECTED state.

In step 1002, a wireless device may leave a connected state with anetwork. A wireless device may leave a RRC_CONNECTED state with anetwork. A wireless device may release RRC_CONNECTED state and enterRRC_IDLE state. A wireless device may suspend (or release with suspend)RRC_CONNECTED state and enter RRC_INACTIVE state.

In step 1003, a wireless device may perform transmission with aconfigured grant. A wireless device may perform the transmission, whilein leaving the connected state. A wireless device may perform thetransmission in RRC_IDLE or RRC_INACTIVE state.

A wireless device, while in leaving a connected state with a network,may perform transmission with a configured grant, wherein configurationof the configured grant may be received from a network. For example, awireless device may use a resource of pre-allocated resource (forexample, configured grant or a SPS configuration) for transmission.According to some embodiments of the present disclosure, a configuredgrant for data transmission while in leaving a connected state may be aresource of a SPS configuration.

According to some embodiments of the present disclosure, a wirelessdevice may receive configuration of the configured grant before leavingthe connected state. A wireless device may receive configuration of theconfigured grant upon leaving the connected state. A wireless device mayreceive configuration of the configured grant from a network in aconnected state with the network. For example, a wireless device mayreceive configuration of the configured grant in RRC_CONNECTED state.

According to some embodiments of the present disclosure, a wirelessdevice may receive configuration of the configured grant while inleaving a connected state with a network. For example, a wireless devicemay receive a configured grant (or a SPS configuration) in RRC_IDLEstate or RRC_INACTIVE state. For other example, a wireless device mayreceive SPS configuration via system information regardless of RRCstate.

According to some embodiments of the present disclosure, a configurationof a configured grant may include a maximum amount of data supported bythe configured grant. A configuration of a configured grant may includean identity of the wireless device which is used by the wireless devicewhen the wireless device performs uplink transmission with theconfigured grant or downlink reception, while in leaving the connectedstate.

According to some embodiments of the present disclosure, a wirelessdevice, while in leaving a connected state with a network, may select orreselect a cell (for example, a suitable and accessible cell) and campon the cell. The wireless device may receive a configured grant from theselected cell.

In step 1004, a wireless device may perform a random access (RA) to thenetwork, after the TAT is expired. A wireless device may perform a RA tothe network, when the TAT is expired. A wireless device may perform a RAto the network, when the TAT is expired and data (for example, data fortransmitting from the wireless device to the network) becomes available.

A wireless device may release or deactivate a configured grant upon theTAT is expired, while in leaving the connected state. When a TAT isexpired, a wireless device may deactivate to transmit data using theconfigured grant. While deactivating the configured grant, when datafrom the wireless device becomes available, the wireless device may tryto enter a connected state with a network by performing a RA.

A wireless device may initiate uplink transmission of a RRC Requestmessage to enter the connected state with the network. For example, a RAprocedure may include initiating uplink transmission of a RRC Requestmessage.

A wireless device may enter a connected state with a network byperforming a RA to the network, after the TAT is expired. A wirelessdevice may receive reconfiguration of a configured grant. A wirelessdevice may align a time advance and restart or start a TAT.

According to some embodiments of the present disclosure, a wirelessdevice may receive a RRCSetup message. A wireless device may enter aconnected state with a network. A wireless device may receive aconfiguration for resource of transmission. A wireless device mayreceive SPS reconfiguration and new SPS-I-RNTI. A wireless device maytransmit user data in the connected state. A wireless device may performtransmission with the network in the connected state.

According to some embodiments of the present disclosure, a wirelessdevice may be an autonomous driving apparatus in communication with atleast one of a mobile terminal, a network, and/or autonomous vehiclesother than the wireless device.

According to some embodiments of the present disclosure, a wirelessdevice may perform a RA to a network in order to enter a connected state(e.g. RRC_CONNECTED) with the network, when a TAT is expired. Afterentering the connected state, the wireless device may align UL timingwith the network and/or reconfigure the configured grant for datatransmission. Therefore, the wireless device could continue datatransmission.

According to some embodiments of the present disclosure, a wirelessdevice may keep running a TAT when the wireless device leaves aconnected state with a network. A wireless device may use the TAT forchecking validity of a configured grant. When the TAT is expired thewireless device may deactivate the configured grant.

FIG. 11 shows an apparatus for entering a connected state with a networkafter a TAT is expired, according to some embodiments of the presentdisclosure. The description of the same parts as those described abovewill be simplified or omitted. An apparatus may be referred as awireless device, such as a user equipment (UE), an Integrated Access andBackhaul (IAB), or etc.

A wireless device includes a processor 1110, a power management module1111, a battery 1112, a display 1113, a keypad 1114, a subscriberidentification module (SIM) card 1115, a memory 1120, a transceiver1130, one or more antennas 1131, a speaker 1140, and a microphone 1141.

The processor 1110 may be configured to implement proposed functions,procedures and/or methods described in this description. Layers of theradio interface protocol may be implemented in the processor 1110. Theprocessor 1110 may include application-specific integrated circuit(ASIC), other chipset, logic circuit and/or data processing device. Theprocessor 1110 may be an application processor (AP). The processor 1110may include at least one of a digital signal processor (DSP), a centralprocessing unit (CPU), a graphics processing unit (GPU), a modem(modulator and demodulator). An example of the processor 1110 may befound in SNAPDRAGON™ series of processors made by Qualcomm®, EXYNOS™series of processors made by Samsung®, A series of processors made byApple®, HELIO™ series of processors made by MediaTek®, ATOM™ series ofprocessors made by Intel® or a corresponding next generation processor.

The power management module 1111 manages power for the processor 1110and/or the transceiver 1130. The battery 1112 supplies power to thepower management module 1111. The display 1113 outputs results processedby the processor 1110. The keypad 1114 receives inputs to be used by theprocessor 1110. The keypad 1114 may be shown on the display 1113. TheSIM card 1115 is an integrated circuit that is intended to securelystore the international mobile subscriber identity (IMSI) number and itsrelated key, which are used to identify and authenticate subscribers onmobile telephony devices (such as mobile phones and computers). It isalso possible to store contact information on many SIM cards.

The memory 1120 is operatively coupled with the processor 1110 andstores a variety of information to operate the processor 1110. Thememory 1120 may include read-only memory (ROM), random access memory(RAM), flash memory, memory card, storage medium and/or other storagedevice. When the embodiments are implemented in software, the techniquesdescribed herein can be implemented with modules (e.g., procedures,functions, and so on) that perform the functions described herein. Themodules can be stored in the memory 1120 and executed by the processor1110. The memory 1120 can be implemented within the processor 1110 orexternal to the processor 1110 in which case those can becommunicatively coupled to the processor 1110 via various means as isknown in the art.

The transceiver 1130 is operatively coupled with the processor 1110, andtransmits and/or receives a radio signal. The transceiver 1130 includesa transmitter and a receiver. The transceiver 1130 may include basebandcircuitry to process radio frequency signals. The transceiver 1130controls the one or more antennas 1131 to transmit and/or receive aradio signal.

The speaker 1140 outputs sound-related results processed by theprocessor 1110. The microphone 1141 receives sound-related inputs to beused by the processor 1110.

According to some embodiments of the present disclosure, the processor1110 may be configured to be coupled operably with the memory 1120 andthe transceiver 1130. The processor 1110 may be configured to start aTime Alignment Timer (TAT). The processor 1110 may be configured toleave a connected state with a network. The processor 1110 may beconfigured to perform transmission with a configured grant, wherein theconfigured grant is received from the network, while in leaving theconnected state. The processor 1110 may be configured to perform arandom access (RA) to the network after the TAT is expired, while inleaving the connected state.

According to some embodiments of the present disclosure shown in FIG.11, a wireless device may perform a RA to a network in order to enter aconnected state (e.g. RRC_CONNECTED) with the network, when a TAT isexpired. After entering the connected state, the wireless device mayalign UL timing with the network and/or reconfigure the configured grantfor data transmission. Therefore, the wireless device could continuedata transmission.

According to some embodiments of the present disclosure, a wirelessdevice may keep running a TAT when the wireless device leaves aconnected state with a network. A wireless device may use the TAT forchecking validity of a configured grant. When the TAT is expired thewireless device may deactivate the configured grant.

The present disclosure may be applied to various future technologies,such as AI, robots, autonomous-driving/self-driving vehicles, and/orextended reality (XR).

<AI>

AI refers to artificial intelligence and/or the field of studyingmethodology for making it. Machine learning is a field of studyingmethodologies that define and solve various problems dealt with in AI.Machine learning may be defined as an algorithm that enhances theperformance of a task through a steady experience with any task.

An artificial neural network (ANN) is a model used in machine learning.It can mean a whole model of problem-solving ability, consisting ofartificial neurons (nodes) that form a network of synapses. An ANN canbe defined by a connection pattern between neurons in different layers,a learning process for updating model parameters, and/or an activationfunction for generating an output value. An ANN may include an inputlayer, an output layer, and optionally one or more hidden layers. Eachlayer may contain one or more neurons, and an ANN may include a synapsethat links neurons to neurons. In an ANN, each neuron can output asummation of the activation function for input signals, weights, anddeflections input through the synapse. Model parameters are parametersdetermined through learning, including deflection of neurons and/orweights of synaptic connections. The hyper-parameter means a parameterto be set in the machine learning algorithm before learning, andincludes a learning rate, a repetition number, a mini batch size, aninitialization function, etc. The objective of the ANN learning can beseen as determining the model parameters that minimize the lossfunction. The loss function can be used as an index to determine optimalmodel parameters in learning process of ANN

Machine learning can be divided into supervised learning, unsupervisedlearning, and reinforcement learning, depending on the learning method.Supervised learning is a method of learning ANN with labels given tolearning data. Labels are the answers (or result values) that ANN mustinfer when learning data is input to ANN. Unsupervised learning can meana method of learning ANN without labels given to learning data.Reinforcement learning can mean a learning method in which an agentdefined in an environment learns to select a behavior and/or sequence ofactions that maximizes cumulative compensation in each state.

Machine learning, which is implemented as a deep neural network (DNN)that includes multiple hidden layers among ANN, is also called deeplearning. Deep learning is part of machine learning. In the following,machine learning is used to mean deep learning.

<Robot>

A robot can mean a machine that automatically processes or operates agiven task by its own abilities. In particular, a robot having afunction of recognizing the environment and performingself-determination and operation can be referred to as an intelligentrobot. Robots can be classified into industrial, medical, household,military, etc., depending on the purpose and field of use. The robot mayinclude a driving unit including an actuator and/or a motor to performvarious physical operations such as moving a robot joint. In addition,the movable robot may include a wheel, a break, a propeller, etc., in adriving unit, and can travel on the ground or fly in the air through thedriving unit.

<Autonomous-Driving/Self-Driving>

The autonomous-driving refers to a technique of self-driving, and anautonomous vehicle refers to a vehicle that travels without a user'soperation or with a minimum operation of a user. For example,autonomous-driving may include techniques for maintaining a lane whiledriving, techniques for automatically controlling speed such as adaptivecruise control, techniques for automatically traveling along apredetermined route, and techniques for traveling by setting a routeautomatically when a destination is set. The autonomous vehicle mayinclude a vehicle having only an internal combustion engine, a hybridvehicle having an internal combustion engine and an electric motortogether, and an electric vehicle having only an electric motor, and mayinclude not only an automobile but also a train, a motorcycle, etc. Theautonomous vehicle can be regarded as a robot having an autonomousdriving function.

<XR>

XR are collectively referred to as VR, AR, and MR. VR technologyprovides real-world objects and/or backgrounds only as computer graphic(CG) images, AR technology provides CG images that is virtually createdon real object images, and MR technology is a computer graphicstechnology that mixes and combines virtual objects in the real world. MRtechnology is similar to AR technology in that it shows real and virtualobjects together. However, in the AR technology, the virtual object isused as a complement to the real object, whereas in the MR technology,the virtual object and the real object are used in an equal manner. XRtechnology can be applied to HMD, head-up display (HUD), mobile phone,tablet PC, laptop, desktop, TV, digital signage. A device to which theXR technology is applied may be referred to as an XR device.

FIG. 12 shows an example of an AI device to which the technical featuresof the present disclosure can be applied.

The AI device 1200 may be implemented as a stationary device or a mobiledevice, such as a TV, a projector, a mobile phone, a smartphone, adesktop computer, a notebook, a digital broadcasting terminal, a PDA, aPMP, a navigation device, a tablet PC, a wearable device, a set-top box(STB), a digital multimedia broadcasting (DMB) receiver, a radio, awashing machine, a refrigerator, a digital signage, a robot, a vehicle,etc.

Referring to FIG. 12, the AI device 1200 may include a communicationpart 1210, an input part 1220, a learning processor 1230, a sensing part1240, an output part 1250, a memory 1260, and a processor 1270.

The communication part 1210 can transmit and/or receive data to and/orfrom external devices such as the AI devices and the AI server usingwire and/or wireless communication technology. For example, thecommunication part 1210 can transmit and/or receive sensor information,a user input, a learning model, and a control signal with externaldevices. The communication technology used by the communication part1210 may include a global system for mobile communication (GSM), a codedivision multiple access (CDMA), an LTE/LTE-A, a 5G, a WLAN, a Wi-Fi,Bluetooth™, radio frequency identification (RFID), infrared dataassociation (IrDA), ZigBee, and/or near field communication (NFC).

The input part 1220 can acquire various kinds of data. The input part1220 may include a camera for inputting a video signal, a microphone forreceiving an audio signal, and a user input part for receivinginformation from a user. A camera and/or a microphone may be treated asa sensor, and a signal obtained from a camera and/or a microphone may bereferred to as sensing data and/or sensor information. The input part1220 can acquire input data to be used when acquiring an output usinglearning data and a learning model for model learning. The input part1220 may obtain raw input data, in which case the processor 1270 or thelearning processor 1230 may extract input features by preprocessing theinput data.

The learning processor 1230 may learn a model composed of an ANN usinglearning data. The learned ANN can be referred to as a learning model.The learning model can be used to infer result values for new input datarather than learning data, and the inferred values can be used as abasis for determining which actions to perform. The learning processor1230 may perform AI processing together with the learning processor ofthe AI server. The learning processor 1230 may include a memoryintegrated and/or implemented in the AI device 1200. Alternatively, thelearning processor 1230 may be implemented using the memory 1260, anexternal memory directly coupled to the AI device 1200, and/or a memorymaintained in an external device.

The sensing part 1240 may acquire at least one of internal informationof the AI device 1200, environment information of the AI device 1200,and/or the user information using various sensors. The sensors includedin the sensing part 1240 may include a proximity sensor, an illuminancesensor, an acceleration sensor, a magnetic sensor, a gyro sensor, aninertial sensor, an RGB sensor, an IR sensor, a fingerprint recognitionsensor, an ultrasonic sensor, an optical sensor, a microphone, a lightdetection and ranging (LIDAR), and/or a radar.

The output part 1250 may generate an output related to visual, auditory,tactile, etc. The output part 1250 may include a display unit foroutputting visual information, a speaker for outputting auditoryinformation, and/or a haptic module for outputting tactile information.

The memory 1260 may store data that supports various functions of the AIdevice 1200. For example, the memory 1260 may store input data acquiredby the input part 1220, learning data, a learning model, a learninghistory, etc.

The processor 1270 may determine at least one executable operation ofthe AI device 1200 based on information determined and/or generatedusing a data analysis algorithm and/or a machine learning algorithm. Theprocessor 1270 may then control the components of the AI device 1200 toperform the determined operation. The processor 1270 may request,retrieve, receive, and/or utilize data in the learning processor 1230and/or the memory 1260, and may control the components of the AI device1200 to execute the predicted operation and/or the operation determinedto be desirable among the at least one executable operation. Theprocessor 1270 may generate a control signal for controlling theexternal device, and may transmit the generated control signal to theexternal device, when the external device needs to be linked to performthe determined operation. The processor 1270 may obtain the intentioninformation for the user input and determine the user's requirementsbased on the obtained intention information. The processor 1270 may useat least one of a speech-to-text (STT) engine for converting speechinput into a text string and/or a natural language processing (NLP)engine for acquiring intention information of a natural language, toobtain the intention information corresponding to the user input. Atleast one of the STT engine and/or the NLP engine may be configured asan ANN, at least a part of which is learned according to a machinelearning algorithm. At least one of the STT engine and/or the NLP enginemay be learned by the learning processor 1230 and/or learned by thelearning processor of the AI server, and/or learned by their distributedprocessing. The processor 1270 may collect history information includingthe operation contents of the AI device 1200 and/or the user's feedbackon the operation, etc. The processor 1270 may store the collectedhistory information in the memory 1260 and/or the learning processor1230, and/or transmit to an external device such as the AI server. Thecollected history information can be used to update the learning model.The processor 1270 may control at least some of the components of AIdevice 1200 to drive an application program stored in memory 1260.Furthermore, the processor 1270 may operate two or more of thecomponents included in the AI device 1200 in combination with each otherfor driving the application program.

FIG. 13 shows an example of an AI system to which the technical featuresof the present disclosure can be applied.

Referring to FIG. 13, in the AI system, at least one of an AI server1320, a robot 1310 a, an autonomous vehicle 1310 b, an XR device 1310 c,a smartphone 1310 d and/or a home appliance 1310 e is connected to acloud network 1300. The robot 1310 a, the autonomous vehicle 1310 b, theXR device 1310 c, the smartphone 1310 d, and/or the home appliance 1310e to which the AI technology is applied may be referred to as AI devices1310 a to 1310 e.

The cloud network 1300 may refer to a network that forms part of a cloudcomputing infrastructure and/or resides in a cloud computinginfrastructure. The cloud network 1300 may be configured using a 3Gnetwork, a 4G or LTE network, and/or a 5G network. That is, each of thedevices 1310 a to 1310 e and 1320 consisting the AI system may beconnected to each other through the cloud network 1300. In particular,each of the devices 1310 a to 1310 e and 1320 may communicate with eachother through a base station, but may directly communicate with eachother without using a base station.

The AI server 1320 may include a server for performing AI processing anda server for performing operations on big data. The AI server 1320 isconnected to at least one or more of AI devices constituting the AIsystem, i.e. the robot 1310 a, the autonomous vehicle 1310 b, the XRdevice 1310 c, the smartphone 1310 d and/or the home appliance 1310 ethrough the cloud network 1300, and may assist at least some AIprocessing of the connected AI devices 1310 a to 1310 e. The AI server1320 can learn the ANN according to the machine learning algorithm onbehalf of the AI devices 1310 a to 1310 e, and can directly store thelearning models and/or transmit them to the AI devices 1310 a to 1310 e.The AI server 1320 may receive the input data from the AI devices 1310 ato 1310 e, infer the result value with respect to the received inputdata using the learning model, generate a response and/or a controlcommand based on the inferred result value, and transmit the generateddata to the AI devices 1310 a to 1310 e. Alternatively, the AI devices1310 a to 1310 e may directly infer a result value for the input datausing a learning model, and generate a response and/or a control commandbased on the inferred result value.

Various embodiments of the AI devices 1310 a to 1310 e to which thetechnical features of the present disclosure can be applied will bedescribed. The AI devices 1310 a to 1310 e shown in FIG. 13 can be seenas specific embodiments of the AI device 1200 shown in FIG. 12.

In view of the exemplary systems described herein, methodologies thatmay be implemented in accordance with the disclosed subject matter havebeen described with reference to several flow diagrams. While forpurposed of simplicity, the methodologies are shown and described as aseries of steps or blocks, it is to be understood and appreciated thatthe claimed subject matter is not limited by the order of the steps orblocks, as some steps may occur in different orders or concurrently withother steps from what is depicted and described herein. Moreover, oneskilled in the art would understand that the steps illustrated in theflow diagram are not exclusive and other steps may be included or one ormore of the steps in the example flow diagram may be deleted withoutaffecting the scope of the present disclosure.

Claims in the present description can be combined in a various way. Forinstance, technical features in method claims of the present descriptioncan be combined to be implemented or performed in an apparatus, andtechnical features in apparatus claims can be combined to be implementedor performed in a method. Further, technical features in method claim(s)and apparatus claim(s) can be combined to be implemented or performed inan apparatus. Further, technical features in method claim(s) andapparatus claim(s) can be combined to be implemented or performed in amethod. Other implementations are within the scope of the followingclaims.

What is claimed is:
 1. A method performed by a wireless device in a wireless communication system, the method comprising: starting a Time Alignment Timer (TAT); and leaving a connected state with a network; while in leaving the connected state: performing transmission with a configured grant, wherein the configured grant is received from the network; and performing a random access (RA) to the network, after the TAT is expired.
 2. The method of claim 1, wherein the method further comprises, continuing running the TAT, after leaving the connected state.
 3. The method of claim 1, wherein the method further comprises, restarting the TAT, while in leaving the connected state.
 4. The method of claim 1, wherein the configured grant is a resource of a Semi-Persistent Scheduling configuration.
 5. The method of claim 1, wherein the method further comprises, receiving configuration of the configured grant.
 6. The method of claim 5, wherein the configuration is received, while in leaving the connected state.
 7. The method of claim 5, wherein the configuration includes a maximum amount of data supported by the configured grant.
 8. The method of claim 5, wherein the configuration includes an identity of the wireless device for uplink transmission with the configured grant or downlink reception.
 9. The method of claim 1, wherein the method further comprises, while in leaving the connected state: selecting a cell on the network; and camping on the cell.
 10. The method of claim 1, wherein the method further comprises, deactivating the configured grant when the TAT is expired.
 11. The method of claim 1, wherein the RA to the network includes transmitting a RRC Request message to the network.
 12. The method of claim 1, wherein the RA is performed when data becomes available in the wireless device and the TAT is expired.
 13. The method of claim 1, the method further comprising, entering the connected state; and performing transmission in the connected state.
 14. The method of claim 1, wherein the wireless device is an autonomous driving apparatus in communication with at least one of a mobile terminal, a network, and/or autonomous vehicles other than the wireless device.
 15. A wireless device in a wireless communication system, the wireless device comprising: a memory; a transceiver; and a processor, operably coupled to the memory and the transceiver, and configured to: start a Time Alignment Timer (TAT); and leave a connected state with a network; while in leaving the connected state: perform transmission with a configured grant, wherein the configured grant is received from the network; and perform a random access (RA) to the network, after the TAT is expired. 